What rat whiskers can tell us about the sense of touch

Washington, Feb 19 (ANI): Scientists are studying how rats use their whiskers to sense the environment around them to convert the sense of touch with movement.

Rats, using their whiskers, can determine all of an object’s spatial properties, including size, shape, orientation and texture.

“The big question our laboratory is interested in is how do animals, including humans, actively move their sensors through the environment, and somehow turn that sensory data into a stable perception of the world,” said Mitra Hartmann at Northwestern University.

“We don’t understand touch nearly as well as other senses. We know that visual and auditory stimuli can be quantified by the intensity and frequency of light and sound, but we don’t fully understand the mechanics that generate our sense of touch,” she said.

Hartmann’s team developed a light sheet and used a high-speed video to monitor the precise locations of the whiskers as they came in contact with the object and analyze how the rat moves its head to explore different shapes.

This means that the team can now simulate the rat “whisking ” into different objects. The simulations can then be compared against real behaviour, as monitored with the light sheet.

“We show that the bending moment, or torque, at the whisker base can be used to generate three-dimensional spatial representations of the environment,” Hartmann said.

“We used this principle to make arrays of robotic whiskers that in replicate much of the basic mechanics of rat whiskers.”

The model could be used for engineering applications in which vision is limited but more importantly, it would help understand our own behaviour better, she said.

“Although whiskers and hands are very different, the basic neural pathways that process tactile information are in many respects similar across mammals,” Hartmann said.

“A better understanding of neural processing in the whisker system may provide insights into how our own brains process information.”

She will present the study results at the American Association for the Advancement of Science (AAAS) annual meeting in Washington, D.C. (ANI)